This study is all about evaluating the fixed parameter of sacral kyphosis related to pelvic incidence. The parameters of pelvic determine lumber and pelvic spinal position. The study has already defined the normative values which have been evaluated to find out the role of these parameters in the clinical stage. The study is about to measure the ratio of sacral slope and pelvic incidence i.e. SS/PI. For the measurements of pelvic incidence and sacral slope, CT has been made for hundred consecutive patients from the database. Among them, the images without clear landmarks have been removed. Pelvic incidence and sacral kyphosis are being measured using the standardized technique. The result has been found that there is a strong positive correlation between sacral kyphosis and pelvic incidence, as per the studies of 95 patients along with an average age of 51.3 years.

Therefore the study has come to a conclusion that the relation between pelvic incidence and sacral kyphosis exists in a very strong way. It is also reflecting different pelvic morphologies. Sacral kyphosis determines partial sacral slope. If you are going to compare PI with SK relatively, you will find that there is less ability in order to change the ratio of SS/PI.

Ref: https://pubmed.ncbi.nlm.nih.gov/29503685/